1. Field
The present disclosure relates to a motor, and more particularly, to an assembling structure of a motor.
2. Background
FIG. 1 illustrates an example of a motor.
Referring to FIG. 1, a motor 1 includes a rotation shaft 10, a rotor 11 that surrounds the rotation shaft 10, and a detector 12 that detects a rotation angle of the rotor 11. The rotor 11 includes a rotor core 111 that surrounds the rotation shaft 10 and a drive magnet 112 coupled to the rotor core 111. The rotor 11 rotates together with the rotation shaft 10 by interaction with a stator (not shown) fixed to a housing (not shown).
The detector 12 detects a position of the rotor 11, i.e., a position of the drive magnet 112. To this end, the detector 12 may include a sensor magnet 121 and an encoder integrated chip (IC) 122. The sensor magnet 121 emits flux or polarity according to rotation of the rotation shaft 10 and the rotor 11, and the encoder IC 122 detects the flux or polarity emitted by the sensor magnet 121, thereby detecting rotation of the rotor 11.
To this end, the sensor magnet 121 may be mounted in a recessed portion formed in one end of the rotation shaft 10. An assembling structure of the sensor magnet 121 and the rotation shaft 10 will be described with reference to FIG. 2, which is an enlarged view of a portion A of FIG. 1.
Referring to FIG. 2, an edge A′ of the sensor magnet 121 has a round shape. Thus, an assembling portion of the rotation shaft 10 that contacts the edge A′ of the sensor magnet 121 also has a round shape.
As the usage period of the motor 1 increase, the assembling portion of the rotation shaft 10 on which the sensor magnet 121 is mounted, may be worn out. If the assembling portion of the rotation shaft 10 is worn out, a gap may be formed between the sensor magnet 121 and the rotation shaft 10. Thus, the sensor magnet 121 cannot be solidly fixed to the rotation shaft 10, and magnetism of the sensor magnet 121 leaks such that a degree of precision of detection may be lowered.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.